Refrigerator car



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REFRIGERATOR CAR Filed Feb. 4, 1929 5 Sheets-Sheet 5 .fa/627252 690i* e HM gym Patented Apr. 12, 1932 UNITED STATES PATENT OFFICE GEORGE A. HULL, OF CHICAGO, ILLINOIS, ASSIGNOB, TO EQUIPMENT SPECIALTIES COMPANY, F CHICAGO, ILLINOIS, .A CORPORATION OF ILLINOIS REFRIGERATOR CAR Application led February 4, 1929. Serial No. 337,291.

The present invention relates to refrigerator cars, and is more particularly concerned lfl with floors for refrigerator cars and the like. It has been customary in refrigerator cars to provide a false bottom, which encloses a plurality of layers of heat insulating material, such as asbestos paper, ber, fabric or the like, and a layer of plastic waterproof compound above the insulating material and below the floor, primarily-for the purpose of preventing water from seeping through the floor into the insulation.

In the refrigerator cars of the prior art, it has been necessary, however, to pierce this waterproof layer at a plurality of points with nails for the purpose of securing the car flooring in place above the compound, and the presence of nails, bolts andother fastening means passing through the Waterproofing defeats the purpose of the waterproofing and permits the water to seep through into the fi rous insulation.

This matter is of particular importance in the shipment of lettuce and other products where it has become the practice to pile ice in the main portion of the car among the boxes in order to keep the product in the best condition, and this practice is ordinarily termed body icing.

The water Iresulting from the melting of the ice placed in the main part of the car seeps through the flooring and points of perforation of the waterproof layer, and as a result the insulation soon becomes Vwaterlogged and practically useless as a heat insulator, since its insulating quality depends in a large measure upon the presence of the dead air spaces between the insulating fibers.

When the insulation is in this condition it may also become frozen, and the alternate thawing and freezing of the waterlog ed insulation and the timbers causes great eterioration of the floor structure, and .the maintenance of the vfloor has been very expensive in the cars of the prior art. The stringers and adjacent parts tend to split and rot, and when the wood and insulation has once become wet it remains so due to the fact that it Vis so enclosed as to prevent evaporation due to ventilation.

One of the objects of the present invertof the Hoor after it has been wet by body icing or otherwise.

Another object of the invention is the provision of a novel method of securing the flooring in refrigerator cars'with a minimum of labor and withou-t producing perforations' in the waterproofing layer below the flooring.

Another object is the provision of a novel threshold and flooring structure for refrigerator cars whereby the flooring may be irmly secured at the doors without nailing through the waterproofing and whereby the car is adapted to drain over the sills without seeping int-o the insulation.

Another object is the provision of a novel bulkhead supporting structure which permits the ventilation beneath the flooring and which requires no bolts passing through the water-'proofing layer of the floor.

Another object of the invention is the provision of a refrigerator car structure having a novel method of ventilation for the purpose of drying out the flooring when the car is run ning without ice' and underl ventilation.

Another object is the provision of a novel insulated ioor construction which may be more economically constructed due to the elimination of one or more layers of 'false flooring required in the structures of the prior art.

Other objects and advantages will be apparent from the following description and from the accompanying drawings in which present invention, showing the complete ventilating system;

Fig. 2 is a transverse section of the flooring showing the construction of the iioor at the threshold and side wall;

j Fig. 3 is a similar' section taken just inside the ice compartment looking toward the main compartment with the bulkhead removed;

Fig. 4 i's a planview of a portion of the flooring adjacent the threshold;-

Fig. 5 is a detail sectional view through the tiooring at the threshold;

Fig. 6 is a detail sectional view of the floor construction adjacent a side wall;

Fig. 7 is a section view through the floor construction taken longitudinally of the car at the post bearing rail;

e Fig. 8 is a view similar to Fig. 4, showing a modified form of threshold construction;

Fig. 9 is a view similar to Fig. 4, sho-wing a modified construction;

Fig. 10 is a view similar to Fig. 5 of the same modified construction.

Referring to Fig. 1, 1() indicates the refrigerator car in its entirety, but as the invention relates particularly to the floor construction, the embodiment shown is to be regarded as merely exemplary of one of the possible forms which the invention may take. The exact details of the rest o-f the refrigerator car may vary considerably within the scope of the present invention, and many of the details illustrated may be eliminated entirely while still utilizing the important features vof the invention as set forth in the appended claims.A With regard to the Ventilating system of the car for drying out the flooring when the car is running Without ice under ventilation, the car should be provided with ventilation openings 11 and 12 adjacent each end of the car and communicating through the chambers 13 and 14 with a ventilation conduit 15 beneath the flooring .16. In the modern refrigerator car construction which is adapted both for body icing and for use .with ice piled in ice chambers, the ventilation openings 11 and 12 may consist of hatchways leading to the icechambers 13 and 14 respectively, and located at the ends of the car, but other forms of ventilation openings may be employed as well with the ventilation .conduit underneath the flooring.

When it is desired to dry out the flooring, the closures 17 and 18 of the hatchways 11 and 12 may be propped open as shown in the dotted line positions in such manner that the travel of the car will cau-'se the air to flow down one hatchway and up out of the other, and at least a portion of the air will pass through the conduit 15 beneath the flooring, drying out the flooring 16.on its underside and tending to keep the boards in good condition. The direction of the air currents when the car is travelling to the left in Fig. 1 is indicated by the curved arrows.

Since the present invention relates particularly to floor construction, and since the walls and ceiling of the car may take any conventional form, the walls and ceiling have been diagrammatically illustrated, and it is sufcient to say that it includes the usual side walls 19 and 20, end Walls 21 and 22 and ceiling 23, and the car is customarily provided with door openings 24 located adjacent the Vmiddle of the car on each side and having insulated doors 25 and 26, all exterior parts of the car being provided with the usual heat insulation. The car is provided adjacent each end with a bulkhead 27, 28 preferably comprising a plurality of she-et metal sections having channels 29 at their edges forming columns for the support of the bulkhead and for the support of a wooden wall 30. The sheet metal sections 29 are provided with the usual Ventilating openings 31 adjacent the top of the ice chambers 13 and 14 and communicating with the main compartment 32 and with the ventilation openings at 33 below the ice chamber between the columns 29.

The ice chambers 13 and 14 formed by bulkheads 27 and 28 are provided with waterproof drainage pans 34 located beneath the icegrating 35, and substantially lower than the lowest portion of the waterproof layer 36 beneath the flooring 16. The drainage pans 34 are provided with well traps 37 which permit the water to drain out of the pans, but prevent the air from entering.

Referring to Figs. 2 and 6, the construction ofthe car floor is here illustrated in detail. The supporting structure for the floor Aincludes the usual side sills 38 extending longitudinally of the car, and a plurality of intermediate sills 39, which may support a false flooring 40 for the purpose of forming a plurality of dead air spaces 41. The side sills 38 may be provided with a Z-bar 42,

having one flange 43 disposed beneath the sills 38, and the opposite' flange 44 adapted to support the false flooring 40.

Above the false flooring 40 the car may be provided with a plurality of stringers 45 of sufficient thickness to lie flush with the tops of the sills 38 and located above the Z-bars 42 and sills 39 respectively. If desired, the dead air space 41 may be filled with heat insulating material, such as asbestos paper, fabric, etc., secured to the strin ers 45 in the usual manner, but the prefera le construction consists in covering the stringers 45 with a layer 46 of relatively stili heat insulating -material or board form insulation, such as If desired, the layer 46 of heat insulating material may consist of-a plurality of sheets of board form insulation laid one above the other as shown in Fig. l() of the drawings, thereby eliminating the heat insulating material, such as asbestos paper, fabric, etc., which is usually placed in the dead air space 41. This modified construction will be described in detail hereinafter. A

Above the heat insulating layer 46 the car vfioor is provided with a layer of waterproof felt, and an upper layer 49 of asphaltum or other pliable waterproof material covering and impregnatin the roofing felt, and the two layers described are continued upward at the side and' end walls of the car, forming an upwardly extending waterproof layer 50 in each of the outside walls. The waterproof layer described hardens on cooling into asolid body of s'uiicient compressive strength to supporta portion of the load, but it also has suiicient flexibility to prevent cracking at the lower extremes of temperature.

Other forms of waterproof layerswhich may be employed are layers of copper, zinc, galvanized iron, or other metal formed as illustrated in the drawings and extending upward on the sides of the car to form a metal pan beneath the flooring.

The loorino` 16 is located above the waterproof layer 47, and is maintained in spaced relation to the waterproof layer by means of a plurality of spacing members 51, which may consist of relatively thin strips of wood extending in the same direction as the stringers 45 and preferably located above the stringrs 45 to be most effectively supported therey'.

The flooring 16 may consist of a plurality of boards of any form, but tongue and groove ooring is preferably employed in brder to provide a relatively strong construction in which the separate boards are firmly connected to each other and to the car. If desired, the flooring 16 may be provided with a plurality of small `holes for facilitating drainage, the holes being bored at random after the ear has been constructed, and at the points where the water may gather on the top of the flooring. l One of the most important features of the present invention consists in the securing ofthe ooring 16 as well as the spacers 51 without the use of nails, screws or bolts driven through the waterproof layer 47 into the stringers 45 as has been the custom in the refrigerator cars of the prior art. No nails are driven through the iooring or spacer strips, but the liooring is secured at its ends adjacent the walls and threshold of the car r and the spacer strips 51 may be maintained in position by the pressure of the flooring, coniining the strips between the waterproof layer and the ooring.

In order to secure the flooring together in sections so that the sections may be removed as a unit, the flooring may be provided with channeled metal members 100 having a web 101 and side flanges 102 and the channeled members 100 may be secured to the flooring by a lurality of bolts 103. Theweb 101 of the channeled members 100 is of suiiicient width so that the spacers 51 may be received between the side flanges 102, and the side fianges 102 are thereby adapted to definitely position the spacers 51 above the stringers. The ends of the channeled members 100 are preferably beveled as at 104 so that they project vbeyond the edge of the last board in a section and as each end is beveled at the same angle, the ends of the channeled members will fit against each other and extend beneath the boards of the adjacent sections,

thereby aligning the different sections of Y flooring as shown in Fig. 4.

If desired, the flooring may be secured together in sections by means of the spacers 51, or in some embodiments of the invention the-separate boards may be secured solely at their ends, and the spacers 51 may be held in proper position by the pressure of the ooring and by adhesion of the' spacers to the waterproof layer beneath the flooring.

The flooring 16 may be secured at its ends adjacent the side walls by a securing member 52 adapted to engage the top of the flooring at the end, and alsopreferably engaging the ends of the flooring to prevent injury to the waterproofing 50. The securing member 52 may consist of a wooden rail which is -rabbeted as at 53 and provided with la downwardly extending portion or liange 54 adapted to be received between the ends of the flooring 16 and the waterproofing 50.

The rail 52 extends from the door post to the end of the car and after the ooring has been put in place and the crevices 55 and 56 have'been filled with asphaltum,.the rail 52'may be wedged in between the wall studs 57 and the ends of the iiooring 16, clamping the iooring firmly in place and clamping-the waterproofing l50 to the 'studs 57. The rail 52 issecured to the studs by a plurality of bolts 58 and it may also be .rabbeted at 59 and 60 to receive a plurality of wall boards 61 and 62, forming the If waterproofing fabric is used, it is preferably bent upward at 63 forming a curve with a considerable radius to prevent cracking and the space on both sides of the curved portion 63 at 55 and 56 is filled in with asphaltum.

It will thus be observed that the flooring 16 may be secured at its ends without the use of any nails or -other securing devices perforating the' waterproof layer, and furthermore, the floor maybe put in place with a minimum of expenditure of time and labor. The waterproof layer not only extends underneath the flooring, but upward on the walls of the car to a point past the probable water line and the corners of the waterproofing are given additional protection in the form of a filling of asphaltum in thevacant spaces at the ends of the boards.

The upper surface of the stringers may be sloped slightly from the middle of the car toward the ends to facilitate drainage, if desired, and the air ventilation conduit 15 is adapted to permit the drying out of the lower side of the flooring when the car is travelling under ventilation.

At the door openings 24, it is not desirable to employ the securing rails 52 for securing the flooring 16 in place, but the flooring may be secured at its ends by the threshold plates shown in Figs. 2, 4 and 5, in a similar manner without obstructing the doorway. The waterproofing layer 47 may be bent upward adjacent the door posts 64 and extended outward over the sill 38 at the doorway, and bent downward as at 65 outside of the sill. The cracks about the door posts 64 are preferably filled with asphaltum, and the threshold is provided with a wooden filler strip 66 beneath the threshold at the ends of the flooring 16.

The threshold plate 67 comprises a sheet metal member having a downwardly extending flange or apron 68 adapted to form a facing for the car wall beneath the door opening 24, protecting the sill 38 and clamping the waterproof layer against the sill by means of the bolts 69, which also secure the Z-bars 42. The threshold plate 67 is also provided with a flange 70 extending inward from the apron 68 and upward at a slight angle to form a tapered door opening which Ymay be sealed by means of the usual doors having inwardly tapered edges.

At the point 71 adjacent the ends of the flooring 16, the threshold plate 67 is bent upward to cover the ends of the flooring, and at 72 it is bent inward at right angles to form an attaching flange 73, and the attaching flange is preferably secured flush with the upper edge of the flooring 16 by a plurality of relatively short screws 74.

The threshold plate 67 is extended beyond the doorpost 64 at each side of the door as at 75, in order to secure the flooring immediately opposite the door post 64, and the threshold plate may be provided with yupwardly extending flanges 105 adapted to be bolted to the door post 64. The waterproofing layer 47 is extended upward between the flanges 105 and the door post 64 and clamped between the flange and the door post at 106. The upwardly extending portion of the waterproof layer 50 is clamped between the door post and the rail 52, and in edect a complete waterproof pan or receptacle is provided extending upward on the walls of the car at all points except at the threshold where the pan drains outover the sill.

Referring to Fig. 8, a modified form of threshold plate is illustrated in this figure, in which the threshold plate is adapted to extend longitudinally into a slot 76 in the ends of the flooring adjacent the door. The flooring may then be protected by a separate metal strip 77 secured by screws 78.

Referring to Figs. 1, 3 and 7, another feature of the present invention is the floor construction beneath the bulkhead 27, by means of which all bolts or other fastening means passing through the waterproof layer are eliminated. For this purpose, the car may be provided with a post bearing rail 7 9 comprising an elongated sheet metal member having a downwardly extending flange 80 adapted to overhang the drainage pan 34 and adapted to reinforce the post bearing rail.

The post bearing rail is provided at each end with upwardly turned attaching flanges 82, which may be secured to the studs or side walls by a plurality of bolts 81, and the bolts 81 may likewise secure the floor securing rail 52 in place.

The body portion 83 of the post bearing rail preferably slopes downward toward the drainage pan 84 for the purpose of facilitating the drainage of any water which may be above the flooring 16, and the last board 84 of .the flooring may be tapered to permit the slope of the bearing rail. The body portion 83 of the post bearing rail provides a support to which the column 29 of the metal bulkhead sections may be secured by means of the usual flanged feet, and it is unnecessary to extend any bolts through the wooden post bearing rail 85, thereby' maintaining the waterproof layer 47 imperforate at all points.

The Awaterproof layer 47 is preferably curved downward over an arc of considerable radius at 86 overlapping the upwardly extending flange 87 of the drainage pan 34 at 88, and the downwardly extending flange 80 of the post. bearing rail clamps the waterproofing in place against the side of the drainage pan 34. The crevices 89 adjacent the curved portion 86 of the waterproofing layer are filled with asphaltum, and the asphaltum layer may be extended through the apertures 90 which are provided in the flange to connect the air conduits 15 with the drainage pan 84.

Referring to Figs. 9 and 10, a modiiied form is illustrated in these figures, from which the usual fabric insulation of the oor has been entirely eliminated. The board form insulation 46 in this embodiment comprises a plurality of layers of .the material illustrated in the previous figures, laid over the stringers to cover the entire floor area.

The separate layers of board form insulation are laid with broken joints wherever joints are necessary and nailed directly to the stringers forming an insulating layer which may be approximately two inches thick. The thickness of the layer will vary with .the heat insulating value of the board form in# sulation selected, but the layer should be of sufiicient thickness to provide substantially equivalent or better heat insulation than that employed in the present construction where heat insulating fa ric is used in the dead air spaces. The other details: of construction may be substantially the same as previously described.

The operation of the referigerator car in the drying out or ventilation of the flooring has been alreadyV described. It will be evident-that since the entire iioor area is covered with an imperforate layer of waterproofing material overhanging the drainage pans and overhanging the threshold and extending upward on the side walls, it is practically imposible for any water to seep through the waterproof material into the heat insulation and the heatinsulating quality of the insulation is maintained at all times. Furthermore, the stringers and adjacent parts are V"not subjected to waterlogging or rotting as in the floor constructions of the prior art, and the flooringitselfis maintainedy in good condition by drying out the ooring whenever the car is running without ice under ventilation. The use of asphaltum applied directly to one side of the board type insulation provides a waterproofed insulation which is maintained in good condition even though water may penetrate to the edges of the insulation and the usel of this Acom-V posite material eliminates a large amounto labor involved in installing the fabric type insulation between the stringers, thereby greatly reducing the cost of construction.

While I have illustrated a preferred embodimentof my invention, many modifica-l tions may be made without departing from the spirit of the invention, and I do not` wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claims. A

Having thus described my invention, what I claim is new and desire to secure by Letters Patent of the United States, is:

1. In a refrigerator car floor construction,

the combination of sills with a layer of heat insulating material carried by said sills, an imperforate layer of waterproofing material carried by said heat insulating material, a layer of flooring above said waterproofing and spacers between said flooring and waterproofing for forming a ventilation conduit between said waterproofing material and iooring, said ooring extending to a point adjacent the-oppositely located ice chambers in said refrigerator car and said conduits being open at each end, whereby a circulation of air is permitted from said ice chambers through said conduit.

2. In a refrigerator car iioor construction, the combination of sills with a layer of stiff heat insulating material carried by said sills, a layer of waterprooiing material carried by said heat insulating material and extending over a threshold, flooring supported above said waterproofing layer and a threshold plate adapted to engage said iiooring adja- -cent said threshold to secure said ooring in place.

3. In a refrigerator car floor construction, the combination of sills with a layer of stiii heat insulating material carried by said sills, a layer of waterproofing material carried by said heat insulating material and extending over a threshold, fiooring supported above said waterproofing layer and a threshold plate adapted to engage said iiooring adjacent said threshold to secure said flooring in place, and spacers between said flooring and Waterproofing and located above said sills to support said iiooring and form a ventilation conduit.

4. In a refrigerator car floor construction, the combination of sills with a layer of stiff heat insulating material carried by said sills, a layer of waterproofing material above said heat'insulating layer and extending upward at a car wall, a layer of iooring and a .iioor securing member engaging above said i'iooring and secured to said wall.

5. In a refrigerator car iioor construction, the combination of sills with a layer of stili heat insulating material carried by said sills, a layer of waterproofing material above said heat insulating layer and extending upward at a car wall, a layer of flooring and a iioory securing member engaging above said floorlng and secured to said wall, said ioor securing member also being adapted to engage the.

ing said ooring in place on said waterproof ing layer. 7. In a refrigerator car, the combination of a floor supporting structure and walls with bulkheads forming ice chambers, an imperforate waterproof layer on said structure and extending upward on said walls, flooring on said waterproof layer and extending to points adjacent said bulkheads, a iiooring securing member carried by said walls and confining said flooring in place on said waterproofing layer, and spacers between said iiooring and said waterproof layer to forma ventilation conduit extending from one bulkhead to the other, said conduit being open at both ends to permit circulation of air from said ice chambers.

8. In a refrigerator car, the combination of a iioor supporting structure and walls with a layer of waterproofing material over said supporting structure, an ice chamber having a drainage pan in said car, a bulkhead between said ice chamber and the balance of said car, a post bearing rail having support at the walls of said car, said, bulkhead being carried in part by said post bearing rail, a layer of flooring interposed between said post bearing rail and said waterproofing, and spacers beneath said flooring forming a ventilation conduit.

9. In a refrigerator car, the combination of a ioor supporting structure and walls with a layer of waterproofing material over said supporting structure, an ice chamber having a drainage pan in said car, a bulkhead between said ice chamber and the balance of said car, a post bearing railihaving support at the walls of said car, said bulkhead being carried in part by said post bearing rail, a layer of iiooring interposed between said post bearing rail and' said waterproofing, spacers beneath said flooring forming a ventilation conduit, and a flange carried by said post bearing rail overhanging said drainage pan, said ange having openings to said ventilation conduit.

10. A refrigerator car iioor construction comprising the combination of a plurali tv of sills. with 'a covering of integral board form heat insulation extending from one side of the car to the other side carried by said sills and' secured thereto forming a supporting sur'.- face and forming the major heat insulation for .said Hoor. and an imperforate layer of Waterproofing material carried b v and extending over said board form insulation and l protecting said insulation from water.

11. A refrigerator car floor construction comprising the combination of a plurality of sills. with a covering of board form heat insulation carried by and extending over said sills and secured thereto forming a supporting surface and forming the maior heat insulation for said Hoor, and an imperforate laver of waterproofing material carried bv said board form insulation and protecting said insulation from water, said covering comprising a plurality of lavers of stiff insulating material secured to the upper surface of said sills.

12. A refrigerator oar ioor construction comprising the combination of a plurality of sills, with a covering of board form heat insulation carried' by and extending over said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, an imperforate layer of waterproofing material carried by said board form insulation and protecting said insulation from water, and a layer of flooring supported in .spaced relation to said Waterproofing material to form a ventilation conduit open at both ends between said fiooring andl waterproofing material.

13. A refrigerator car floor construction comprising the combination of a plurality of sills. with a covering of board form heat insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, an imperforate layer of waterproofing material carried by said board form insulation and protecting said insulation from water, and a drain pan forming the bottom of an ice chamber; said' waterproofing material extending continuously over said board form insulation into said drain pan.

14. A refrigerator car floor construction comprising the combination of a plurality of sills, with a covering of board form heat insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, an imperforate layer of waterproofing material carried by said board form insulation and protecting said insulation from water. a drain pan forming the bottom of an ice chamber, said waterproofing material extending continuously over .said board form insulation into said drain pan, and a layer of fiooring supported in spaced relation to said waterproofing material to form a ventilation conduit open at bothy ends between said flooring and waterproofing material.

15. A refrigerator car fioor construction comprising the combination of a plurality of sills,- with a covering of board form heat insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, alayer of waterproofing material carried by said board form insulation and protecting said insulation from water, a drain pan forming the bottom of an ice chamber, said waterproofing material extending continuously over said board form insulation into said drain pan, a layer of flooring supported in spaced relation to said waterproofing material to form a ventilation conduit between said flooring and waterproofing material, and a post bearing rail having a bearing flange resting on said flooring. and having upwardly extending bearing flanges secured to the car walls.

16. A refrigerator car ioor construction insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, a layer of waterproong material carn tecting said insulation from water,

ried 'by said board form insulation and protecting said insulation from water, a drain pan forming the bottom of an icel chamber, said waterproofing material extending continuously over said board form insulation into said drain pan, a layer of flooring supported in spaced relation to said waterproofing material to form a ventilation conduit between said iiooring and waterproofing material, and a railY having a downwardly eX- tending flange overlying the edge of said drain pan and waterproong material and formed with apertures leading to said ventilation conduit.

17. A refrigerator car floor 4construction comprising the combination of a plurality of sills, with a coveringv of board form heat insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, a layer of waterproofing material carried by said .board form insulation and prosaid layer of waterproofing material extending upward on the walls of the car, and a common clampmg member for clamping the waterproof material to said wall and for clamping said iooring down on said waterproof material.

18. A refrigerator car floor construction comprising the combination of a plurality of sills, with a covering of board form heat insulation carried by said sills and secured thereto forming a supporting surface and forming the major heat insulation for said floor, a layer of waterprooing material carried by said board form insulation and protecting said insulation from water, said layer of Waterprooling material extending upward on the walls of the car, and a common clamping member for clamping the Waterproof material to said wall and for clamping said flooring down on said waterproof material, said clamping member being formed with a shoulder for engaging the ends of said iiooring to prevent'longitudinal sliding of said flooring. v

19. In a refrigerator car, the combination of an enclosure, including Walls and roof and having ventilation openings at each end of said car, with a bulkhead located adjacent one end of said car and forming a refrigeration chamber at said end, said refrigeration chamber having a water pan at its bottom, said car having a cargo chamber located on the other side of said bulkhead, a ioor structure including supporting members, an imperforate waterproof layer carried by said supporting members, heat insulation for said oor structure arranged below said waterproof layer and protected thereby,'and a car ooring supported in spaced relation to and above lsaid waterproof layer, said car ilooring extending to a point adjacent said bulkhead forming a conduit op-en at each end between said looring and waterproof layer for drying out said flooring by ventilation through` the openings at each end of said car when the car is traveling under ventilation.

20. In a refrigerator car the combination of an enclosure, including walls and roof and having ventilation openings at each end of said car, with a bulkhead located adjacent one end of said car and Jforming a refrigeration chamber at said end, said refrigeration chamber having a water pan at its bottom, said car having a cargo chamber located on the other side of said bulkhead, a oor structure including supporting members, an imperforate waterproof layer carried by said supporting members, heatinsulation for said ioor structure arranged below said waterproof layer and protected thereby, and a car ooring supported in spaced relation to and above said waterproof layer, .said car iooring extend ing to a point adjacent said bulkhead and forming a conduit open at each end between said iiooring and Waterproof layer for drying out said flooring by ventilation through the openings at each end of said car when the car is traveling under ventilation, said imperforate' Waterproof layer being arranged to drain toward said water panand overlapping said water pan at said bulkhead.

21. In a refrigerator car a floor structure comprising a plurality of supporting sills with a layer of stiE board form insulation formed of fibers of bagasse, carried by said sills and forming the major heat insulation 

